scholarly journals Effect of Climate Changes and Coefficient of Surface Roughness on Soil Loss by Wind Erosion in Some Central and Southern Iraq

2021 ◽  
Vol 8 (2) ◽  
Author(s):  
Mohammad Abdullah Al-Rawi
Keyword(s):  
Surface Roughness ◽  
Soil Loss ◽  
Wind Erosion ◽  
Soil Surface ◽  
Roughness Factor ◽  
General Direction ◽  
Dry Conditions ◽  
Factor C ◽  
The Impact ◽  
Southern Iraq

"act Woodruff and siddoway, 1965, established an equation for the estimation of soil Loss by wind erosion called Wind Erosion Equation (WEQ); solution of this equation gives the maximum amount of wind erosion under certain field conditions and is considered evidence in identifying the necessary methods for treating wind erosion in those conditions (Eltaif et al.,1991). This study aims to find out the extent to which climate change in the Samawah region of southern Iraq and Baghdad in central Iraq over a period of 34 years has affected values of soil losing by wind erosion using equation of (woodruff and siddoway, 1965) and effectiveness of this changes in soil surface roughness factor in reducing or increasing these loss. Two sites were selected located within central and southern regions of Iraq, one in Al-Jadiriya area in Baghdad governorate and the other in Samawah area in Al-Muthanna governorate. The results showed that estimated soil losing for years (1980-2013) in Al-Jadiriya decrease annually by 10-30 kg.hec.-1.year-1, while samawah increase by 240-760 kg.hec.-1.year-1. The effect of surface roughness factor was significant in reducing soil loss during period of study. Roughness factor for ridge (0.5) has reduced soil losing by 2.6 times compared to non-ridge soils (1).The ratio in semi-bridge soil (0.75) was 65%. This is due to the impact of bridge in reducing wind speed and reducing its erosivity. The general direction of soil loss indicates decrease in Al-Jadiriya area and increase in Samawah area with the case of fluctuation in soil loss between high and low of general direction line due to climate factor (C) in general equation of soil loss and it reflects ability of wind erosion, so decreased when wet conditions improved, by increased rainfall, reduced evaporation and increasing when dry conditions dominate Corresponding author: E-mail( [email protected] ) All rights reserved AlMuthanna University"

scholarly journals A Strip-Till One-Pass System as a Component of Conservation Agriculture

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2015
Author(s):  
Iwona Jaskulska ◽  
Kestutis Romaneckas ◽  
Dariusz Jaskulski ◽  
Piotr Wojewódzki
Keyword(s):  
Co2 Emissions ◽  
Soil Loss ◽  
Soil Surface ◽  
Conservation Agriculture ◽  
Plant Residues ◽  
Pass System ◽  
Previous Crop ◽  
Bacteria And Fungi ◽  
The Stability ◽  
The Impact

Conservation agriculture has three main pillars, i.e., minimum tillage, permanent soil cover, and crop rotation. Covering the soil surface with plant residues and minimum mechanical soil disturbance can all result from introducing a strip-till one-pass (ST-OP) system. The aim of this study was to determine the impact of the ST-OP technology on the management of plant residues, soil properties, inputs, and emissions related to crop cultivation. We compared the effect of a ST-OP system against conventional tillage (CT) using a plough, and against reduced, non-ploughing tillage (RT). Four field experiments were conducted for evaluating the covering of soil with plant residues of the previous crop, soil loss on a slope exposed to surface soil runoff, soil structure and aggregate stability, occurrence of soil organisms and glomalin content, soil moisture and soil water reserve during plant sowing, labour and fuel inputs, and CO2 emissions. After sowing plants using ST-OP, 62.7–82.0% of plant residues remained on the soil surface, depending on the previous crop and row spacing. As compared with CT, the ST-OP system increased the stability of soil aggregates of 0.25–2.0 mm diameter by 12.7%, glomalin content by 0.08 g·kg−1, weight of earthworms five-fold, bacteria and fungi counts, and moisture content in the soil; meanwhile, it decreased soil loss by 2.57–6.36 t·ha−1 year−1, labour input by 114–152 min·ha−1, fuel consumption by 35.9–45.8 l·ha−1, and CO2 emissions by 98.7–125.9 kg·ha−1. Significant favourable changes, as compared with reduced tillage (RT), were also found with respect to the stability index of aggregates of 2.0–10.0 mm diameter, the number and weight of earthworms, as well as bacteria and fungi counts.

Wind erosion of microplastics from soils: linking soil surface properties with microplastic flux

2020 ◽  
Author(s):  
Annie Ockelford ◽  
Joanna Bulalrd ◽  
Cheryl McKenna-Neuman ◽  
Patrick O'Brien
Keyword(s):  
Surface Roughness ◽  
Wind Tunnel ◽  
Wind Erosion ◽  
Soil Surface ◽  
Surface Characteristics ◽  
Test Material ◽  
Mineral Particle ◽  
Test Bed ◽  
Transport Pathway ◽  
Soil Surface Roughness

<p>Recent studies of soils in the Alps and Middle East indicate airborne transport of microplastics following wind erosion may be significant.  Where microplastics have been entrained by wind they show substantial enrichment ratios compared to mineral particle erosion.  Further, microplastic shape affects enrichment ratios with those for fibres greater than for microbeads which may reflect the lower density and asymmetric shape of microplastics compared to soil particles. This suggests that terrestrial to atmospheric transfer of microplastics could be a significant environmental transport pathway. However, currently we have very little understanding of how the properties, in particular the surface characteristics, of the sediment which they are being eroded from affects their entrainment potential.</p><p>This paper reports wind tunnel studies run to explore the impacts of soil surface characteristics on microplastic flux by wind erosion.  Experiments were performed in a boundary layer simulation wind tunnel with an open-loop suction design.  The tunnel has a working section of 12.5m x 0.7m x 0.76m and is housed in an environmental chamber which, for this study, was held constant at 20 <sup>o</sup>C and 20% RH. In experiments two types of low density microplastic (microbeads and fibres) were mixed into a poorly-sorted soil containing 13% organics.  The polyethylene microbeads had a size range of 212-250 microns and density of 1.2 g cm<sup>3</sup> and the polyester fibres were 5000 microns long and 500-1000 microns in width with a density of 1.38 g cm<sup>3</sup>.  Microplastics were mixed into the sediment in concentrations ranging from 40-1040 mg kg<sup>-1</sup>. For each experiment, test surfaces were prepared by filling a 1.0m x 0.35m x  0.025m metal tray with the given mixture of test material which was lowered into the wind tunnel such that it was flush with the tunnel floor and levelled. The wind tunnel was then switched on and run with increasing wind speeds using 0.25 m s<sup>-1</sup> increments until continuous saltation occurred.  Soil surface roughness was scanned prior to and after each experiment using a high resolution laser scanner (0.5mm resolution over the entire test section).  Transported soil and microplastic particles were captured in bulk using a 2 cm wide by 40 cm tall Guelph-Trent wedge trap that was positioned 2 m downwind of the test bed. </p><p>Discussion concentrates on linking the changes in soil surface topography to the magnitude of microplastic flux where data shows that there is a correlation between the development of the soil surfaces and overall microplastic flux.  Specifically, soil surface roughness is seen as a significant control on microplastic flux where it has a greater overall effect on microplastic fibre flux as compared to the microplastic beads.  The outcome of this research is pertinent to developing understanding surrounding the likely controls and hence propensity of microplastics to be entrained from soil by wind erosion.  </p>

Wind erosion controls on microplastics from soils: linking soil surface properties with microplastic flux

2021 ◽  
Author(s):  
Annie Ockelford ◽  
Joanna Bullard ◽  
Cheryl McKenna Neuman ◽  
Patrick O'Brien
Keyword(s):  
Surface Roughness ◽  
Wind Tunnel ◽  
Wind Erosion ◽  
Soil Surface ◽  
Surface Characteristics ◽  
Test Material ◽  
Mineral Particle ◽  
Test Bed ◽  
Transport Pathway ◽  
Soil Surface Roughness

<p>Recent studies of soils in the Alps and Middle East indicate airborne transport of microplastics following wind erosion may be significant.  Where microplastics have been entrained by wind they show substantial enrichment ratios compared to mineral particle erosion.  Further, microplastic shape affects enrichment ratios with those for fibres greater than for microbeads which may reflect the lower density and asymmetric shape of microplastics compared to soil particles. This suggests that terrestrial to atmospheric transfer of microplastics could be a significant environmental transport pathway. However, currently we have very little understanding of how the properties, in particular the surface characteristics, of the sediment which they are being eroded from affects their entrainment potential.</p><p>This paper reports wind tunnel studies run to explore the impacts of soil surface characteristics on microplastic flux by wind erosion.  Experiments were performed in a boundary layer simulation wind tunnel with an open-loop suction design.  The tunnel has a working section of 12.5m x 0.7m x 0.76m and is housed in an environmental chamber which, for this study, was held constant at 20 <sup>o</sup>C and 20% RH. In experiments two types of low density microplastic (microbeads and fibres) were mixed into a poorly-sorted soil containing 13% organics.  The polyethylene microbeads had a size range of 212-250 microns and density of 1.2 g cm<sup>3</sup> and the polyester fibres were 5000 microns long and 500-1000 microns in width with a density of 1.38 g cm<sup>3</sup>.  Microplastics were mixed into the sediment in concentrations ranging from 40-1040 mg kg<sup>-1</sup>. For each experiment, test surfaces were prepared by filling a 1.0m x 0.35m x  0.025m metal tray with the given mixture of test material which was lowered into the wind tunnel such that it was flush with the tunnel floor and levelled. The wind tunnel was then switched on and run with increasing wind speeds using 0.25 m s<sup>-1</sup> increments until continuous saltation occurred.  Soil surface roughness was scanned prior to and after each experiment using a high resolution laser scanner (0.5mm resolution over the entire test section).  Transported soil and microplastic particles were captured in bulk using a 2 cm wide by 40 cm tall Guelph-Trent wedge trap that was positioned 2 m downwind of the test bed. </p><p>Discussion concentrates on linking the changes in soil surface topography to the magnitude of microplastic flux where data shows that there is a correlation between the development of the soil surfaces and overall microplastic flux.  Specifically, soil surface roughness is seen as a significant control on microplastic flux where it has a greater overall effect on microplastic fibre flux as compared to the microplastic beads.  The outcome of this research is pertinent to developing understanding surrounding the likely controls and hence propensity of microplastics to be entrained from soil by wind erosion. </p>

Estimation of soil loss with RUSLE during a period of increasing rainfall erosivity (1997-2018) in two-contrasted Mediterranean watersheds (southern Spain).

2021 ◽  
Author(s):  
Juan F. Martinez-Murillo ◽  
José A. Sillero-Medina ◽  
José D. Ruiz-Sinoga
Keyword(s):  
Soil Loss ◽  
Mediterranean Climate ◽  
Geographical Area ◽  
Soil Surface ◽  
Point Of View ◽  
Rainfall Regime ◽  
Rainfall Erosivity ◽  
Spatial And Temporal Variability ◽  
Mediterranean Mountains ◽  
Factor C

<p>During the last 25 years, an increasing rainfall erosivity occurred in South of Spain according to recent studies. This fact may rendered in an increment of the derived threatens from water erosion and, consequently, soil loss processes, one of the main geomorphic agent in that geographical area. This study deals with the application of RUSLE equation in two-contrasted Mediterranean mountainous watershed from 1997 to 2018. Both of them are characterised with very common ecogeomorphologic features from Mediterranean mountains but differs in the rainfall regime: one watershed shows an altitudinal gradient from dry-Mediterranean to subhumid Mediterranean climate, and the other one from semiarid to dry-Mediterranean climate.</p><p>From the methodological point of view, RULSE was applied but some modifications were introduced in its calculation: i) rainfall intensity calculated in 10-minutes instead of 30-minutes for Factor R; ii) vegetation cover estimated by means of NDVI for Factor C; and iii) validation using field inventory of soil surface components.</p><p>The results indicated differences between both watersheds given their different ecogeomorphologic conditions. The precision of using I10 let valuate better the soil loss estimation and its spatial and temporal variability. The validation with the soil surface components obtained better results in the rainiest watershed with more biotic ecogeomorphological conditions. This study is of great useful to detect priority areas to carry out revegetation plans to control erosion and floodings.</p>

scholarly journals Long-Term Impact of Wind Erosion on the Particle Size Distribution of Soils in the Eastern Part of the European Union

Entropy ◽  
2021 ◽  
Vol 23 (8) ◽  
pp. 935
Author(s):  
Lenka Lackóová ◽  
Jozefína Pokrývková ◽  
Jana Kozlovsky Dufková ◽  
Agnieszka Policht-Latawiec ◽  
Krystyna Michałowska ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Wind Erosion ◽  
Fine Particles ◽  
Climatic Factors ◽  
Significant Proportion ◽  
Soil Surface ◽  
The European Union ◽  
The Impact

Wind erosion is the leading cause of soil degradation and air pollution in many regions of the world. As wind erosion is controlled by climatic factors, research on this phenomenon is urgently needed in soil and land management in order to better adapt to climate change. In this paper, the impact of wind erosion on the soil surface in relation to particle size distribution was investigated. Changes in percentage of sand, silt and clay fractions based on historical KPP data (1961–1970), LUCAS data base (2009), and field measurements (2016) were analysed in five cadastral areas impacted by wind erosion (Záhorie Lowlands, Slovakia). With the use of GIS tools, models of spatial distribution of sand, silt, clay and erodible fraction (EF) content were developed based on those measurements. Our findings proved that soil texture change driven by wind erosion could happen relatively quickly, and a significant proportion of soil fine particles may be carried away within a few years. The results indicate that the soil surface became much rougher over the period of more than 50 years, but also that the accumulation of fraction of the silt particles occurred in most of the areas affected by the erosive effect.

Crust formation on sandy savanna cropland soils and their potential to reduce dust emissions

2021 ◽  
Author(s):  
Heleen Vos ◽  
Wolfgang Fister ◽  
Frank Eckardt ◽  
Anthony Palmer ◽  
Nikolaus Kuhn
Keyword(s):  
South Africa ◽  
Wind Erosion ◽  
Dust Emission ◽  
Soil Surface ◽  
Free State ◽  
Management Approach ◽  
Crust Formation ◽  
Dust Emissions ◽  
Soil Crusts ◽  
The Impact

<p>After the conversion to cropland, dust emissions can lead to the degradation of agricultural soil. There are also offsite effects of dust emission due to the impact of dust on climate, human health, and global biogeochemistry. The sandy croplands in the Free State of South Africa have been identified by Eckardt et al. (2020) as one of the main dust sources in South Africa. The Free State is a semi-arid province that is dominated by grassland plains and 31% of the land is utilized for agriculture. The emission of dust from sandy Luvisols and Arenosols, which are typically used for crop farming, is mainly controlled by the cropping cycle. In general, the fields are left bare from at least July until December. When the fields have low surface roughness and stubble cover, the presence of physical soil crusts could be one of the main factors protecting the surface against wind erosion. Crusts can form before or during the growing season, before the vegetation cover is too extensive and protects the soil from raindrop impact. The aim of this study was to investigate the occurrence and strength of physical soil crusts on cropland soils in the Free State, to identify the rainfall required to form a stable crust, and to test their impact on dust emissions. Crust strength was measured using a fall cone penetrometer and a torvane, while laboratory rainfall simulations were used to form experimental crusts. Dust emissions from non-crusted and crusted soils were measured and compared with a Portable In-Situ Wind Erosion Laboratory (PI-SWERL).</p><p>Our results show that crusts with sufficient strength to limit dust emissions form on bare Arenosols and Luvisols in the field, illustrating their potential impact on dust emissions. The laboratory rainfall simulations showed that stable crusts could be formed on these soils by 15 mm of rainfall, which is a common amount for single events during the rainy season in the Free State. The PI-SWERL experiments illustrated that the PM10 emission flux of such crusted soils is between 0.14% and 0.26% of that of a non-crusted Luvisol and Arenosol, respectively. The presence of loose sand on the crust acts as an abrader and can increase the emissions up to 4% and 8 % of the non-crusted dust flux. Overall, our study shows that crusts in the field are potentially strong enough to protect the soil surfaces against wind erosion during a phase of the cropping cycle when the soil surface in not protected by plants. These conclusions are not limited to the converted grasslands in the Free State. This indicates that applying farming techniques on croplands that protect crusts or enhance crust formation could be considered as soil management approach to minimize dust emission from dryland sandy soils.</p>

scholarly journals The impact of standard preparation practice on the runoff and soil erosion rates under laboratory conditions

Solid Earth ◽  
2016 ◽  
Vol 7 (5) ◽  
pp. 1293-1302 ◽  
Author(s):  
Abdulvahed Khaledi Darvishan ◽  
Vafa Homayounfar ◽  
Seyed Hamidreza Sadeghi
Keyword(s):  
Soil Erosion ◽  
Soil Loss ◽  
Soil Surface ◽  
Sediment Concentration ◽  
Rainfall Simulation ◽  
Natural Soil ◽  
Northern Iran ◽  
Soil Preparation ◽  
Loam Soil ◽  
The Impact

Abstract. The use of laboratory methods in soil erosion studies, rainfall simulation experiments, Gerlach troughs, and other measurements such as ring infiltrometer has been recently considered more and more because of many advantages in controlling rainfall properties and high accuracy of sampling and measurements. However, different stages of soil removal, transfer, preparation and placement in laboratory plots cause significant changes in soil structure and, subsequently, the results of runoff, sediment concentration and soil loss. Knowing the rate of changes in sediment concentration and soil loss variables with respect to the soil preparation for laboratory studies is therefore inevitable to generalize the laboratory results to field conditions. However, there has been little attention given to evaluate the effects of soil preparation on sediment variables. The present study was therefore conducted to compare sediment concentration and soil loss in natural and prepared soil. To achieve the study purposes, 18 field 1 ×  1 m plots were adopted in an 18 % gradient slope with sandy–clay–loam soil in the Kojour watershed, northern Iran. A portable rainfall simulator was then used to simulate rainfall events using one or two nozzles of BEX: 3/8 S24W for various rainfall intensities with a constant height of 3 m above the soil surface. Three rainfall intensities of 40, 60 and 80 mm h−1 were simulated on both prepared and natural soil treatments with three replications. The sediment concentration and soil loss at five 3 min intervals after time to runoff were then measured. The results showed the significant increasing effects of soil preparation (p ≤ 0.01) on the average sediment concentration and soil loss. The increasing rates of runoff coefficient, sediment concentration and soil loss due to the study soil preparation method for laboratory soil erosion plots were 179, 183 and 1050 % (2.79, 2.83 and 11.50 times), respectively.

scholarly journals The Impact of Farming and Land Ownership on Soil Erosion

2014 ◽  
Vol 62 (5) ◽  
pp. 883-890
Author(s):  
Olga Čermáková ◽  
Miloslav Janeček ◽  
Andrea Jindrová ◽  
Jan Kořínek
Keyword(s):  
Soil Erosion ◽  
Soil Loss ◽  
Large Scale ◽  
Research Area ◽  
Water Erosion ◽  
Small Scale ◽  
Slope Length ◽  
The Difference ◽  
Factor C ◽  
The Impact

The aim of this paper was to compare two methods of farming, especially their effect on water soil erosion. The examined methods were (1) large-scale farming, where more than 50% of the land was leased, and (2) small-scale farming, where the land was almost exclusively privately owned. The research area was 8 cadastres in the district of Hodonín, South Moravia, Czech Republic. In these cadastres 48 land blocks representing both large-scale and small-scale farming (i.e. owners and tenants) were chosen. The long-term average annual soil loss caused by water erosion (G) was calculated using the erosion model USLE 2D and ArcGIS 10.1. The nonparametric Mann-Whitney test was used for the statistical evaluation of the data. The difference between the soil loss (G) on land blocks farmed by small producers (owners) and large producers (tenants) was significant (p < 0.05). Differences between the values of the cropping-management factor (C) were not statistically significant (p = 0.054). Based on the analysis of other variables in the USLE equation it can be stated that a continuous slope length, conditioned by the size of land blocks, played an important role in the amount of soil loss caused by water erosion. Above all, to protect the soil from erosion and maintain soil quality it is necessary to reduce the size of land blocks farmed by tenants and improve the crop rotation systems.

scholarly journals IMPACT OF LAND USE CHANGE TO THE SOIL EROSION ESTIMATION FOR CULTURAL LANDSCAPES: CASE STUDY OF PAPHOS DISRICT IN CYPRUS

2017 ◽  
Vol XLII-5/W1 ◽  
pp. 25-29 ◽  
Author(s):  
B. Cuca ◽  
A. Agapiou
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Land Use Change ◽  
Urban Areas ◽  
Soil Loss ◽  
Cultural Landscapes ◽  
Productivity Level ◽  
Cover Factor ◽  
Factor C ◽  
The Impact

In 2006 UNESCO report has identified soil loss as one of the main threats of climate change with possible impact to natural and cultural heritage. The study illustrated in this paper shows the results from geomatic perspective, applying an interdisciplinary approach undertaken in order to identify major natural hazards affecting cultural landscapes and archaeological heritage in rural areas in Cyprus. In particular, Earth Observation (EO) and ground-based methods were identified and applied for mapping, monitoring and estimation of the possible soil loss caused by soil erosion. Special attention was given to the land use/land cover factor (C) and its impact on the overall estimation of the soil-loss. Cover factor represents the effect of soil-disturbing activities, plants, crop sequence and productivity level, soil cover and subsurface bio-mass on soil erosion. Urban areas have a definite role in retarding the recharge process, leading to increased runoff and soil loss in the broader area. On the other hand, natural vegetation plays a predominant role in reducing water erosion. The land use change was estimated based on the difference of the NDVI value between Landsat 5 TM and Sentinel-2 data for the period between 1980s’ until today. Cover factor was then estimated for both periods and significant land use changes were further examined in areas of significant cultural and natural landscape value. The results were then compared in order to study the impact of land use change on the soil erosion and hence on the soil loss rate in the selected areas.

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